/**
* @author AlbertDarren
* @contact 2563491540@qq.com
*/
#include <iostream>
#include <string>
#include <cstring>
using namespace std;

int main_20()
{
    string str1,str2(5,'a');
    string str3(str2);
    string str4(str3.begin(),str3.begin()+str3.size()/2);
    cout << str1 << endl;
    cout << str2 << endl;
    cout << str3 << endl;
    cout << str4 << endl;
    char str5[]="apple";
    char *str6="pear";
    string str7(str5+1,3);
    string str8(str5,2,2);
    string str9(str5,2,8);
    cout << str7 << endl;
    cout << str8 << endl;
    cout << str9 << endl;
    cout << sizeof(str5)/sizeof(str5[0]) << endl;
    cout << strlen(str5) << endl;
    cout << strlen(str6) << endl;
	return 0;
}
